U-02

TRIM
READOUT
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Manual

  1. TRIM shows the waveform of your audio file so you can pick exactly the range you want and export it as a new file.

  2. It's useful for removing dead air at the start or end, or for cutting a short clip — a ringtone, a preview snippet, anything. Processing happens entirely in your browser; the file is never uploaded.

  3. How to use it (range mode): drag the handles on the waveform, or type the start/end fields directly in mm:ss.mmm format (e.g. 01:05.234). Use the "Preview" button to play back just the selected range before exporting.

  4. Conditions for a lossless export: WAV / FLAC / AIFF can be cut sample-accurately, so they're exported losslessly (stream copy, `-c copy`). Compressed formats like MP3 / AAC (M4A) / OGG can only be cut on compression-frame boundaries, so they're re-encoded in the same format. When re-encoding happens, it's shown in the Readout.

  5. How to use it (remove silence mode): any stretch quieter than the threshold (-60 / -50 / -40dB) lasting at least the minimum silence length (0.5 / 1 / 2 seconds) is cut automatically. Adjust the threshold to match the noise floor of your recording. The Readout compares the length before and after.

  6. Q. Did the exported file's quality change? A. Not for a lossless range export (WAV/FLAC/AIFF). Remove-silence mode, and range trims on compressed formats, go through a decode → re-encode pass because a filter is applied.

  7. Q. Remove silence cut more (or less) than I expected. A. The combination of threshold and minimum silence length changes what counts as "silence". For noisy recordings, try a looser threshold (e.g. -40dB) to catch more.